and/or addition,subtraction made to directory for a certain period of time
without using replication?

We presume you're up to date with latest 2.3 and have configured delta
syncrepl, not slurpd. Avoid slurpd at all costs.

Did I mention avoiding slurpd?

Noppies (Dutch ;)) meaning "No". Adding (2.3.x) a delta syncrepl
provider to your slapd.conf will only cost you a little headache to
configure, you don't need ever to use it for replication, but it will
add records to your changelog DB that will do what you want for searching: